Figure 3.

Residual ${\text{TRE}}_{30}$ for ${\text{XVI}}_{\text{smooth}}$, ${\text{TB}}_{\text{sharp}}$, and TomoTherapy. Boxplots in order of increasing dose from left to right within each plot. Each boxplot represents 100 image registrations. Failures of the automatic registration were considered when ${\text{TRE}}_{30}$ was larger than 3.6 mm. This occurred in 5%–10% of matches over the central clinical dose range. Large errors were observed for low dose on XVI and high dose on TB.